12. A carbon atom
attached to three
other carbon atoms
A carbon atom
attached to four other
carbon atoms
13. CH3
CH3 C
CH3
CH3
C
CH2 CH3
primery
H secondary
tertiary
quaternary
14.
15.
16. This method of nomenclature was used
before 1892.
In this system of nomenclature, the
compounds were named on the basis of
their history, such as source of origin etc.
17.
18. A method known as the Geneva system was
suggested in 1892 by the International Chemical
Congress at Geneva for naming organic
compounds.
Later the International Union of Chemistry at Liege
(Belgium) developed it into IUPAC system of
nomenclature in 1930.
In 1958, the IUPAC system was modified by the
International Union of Pure and Applied Chemistry
(IUPAC) into the present day IUPAC system of
nomenclature.
19.
20. Select the longest continuous chain of carbon
atoms as the parent chain and name the
hydrocarbon.
CH3 CH CH2 CH3
CH3
The longest continuous chain has four carbon
atoms, thus the compound is named as butane.
21. Number the carbon atoms in the longest continuous chain
in such a way as to give lowest possible number to
carbons atoms carrying substituents.
CH3
CH3 CH CH2 CH2 CH3
1 2 3 4 5
CH3
CH3 CH CH2 CH2 CH3
5 4 3 2 1
23. Name the substituent.
Indicate its position by the number of the carbon
atom to which it is attached.
1 2 3 4
CH3 CH CH2 CH3
CH3
The attached group is located on carbon 2 of the
chain, and it is a
24. Prefix the position number and name of the
substituent onto the parent name.
The whole name is written as one word.
Note that the number and name of the substituent
are separated by a hyphen.
1 2 3 4
CH3 CH CH2 CH3
CH3
25. 2- Methyl Butane
Attached alkyl group Longest chain
Position of alkyl group
1 2 3 4
CH3 CH CH2 CH3
CH3
26. If identical substituents are present more than once in
the molecule, then use prefixes di- tri-tetra-,penta-, etc.
Position of each substituent is indicated by a
CH3 CH
CH3
separate number.
CH3
CH2 C
H
CH3
2,4-Dimethylpentane
27. When two or more different substituents are
present, their names are arranged in alphabetic
order and added to the name of the parent alkane,
again as one word.
CH3 CH2 CH
CH3
CH2 CH
CH2
CH2 CH2 CH3
CH3
5-Ethyl-3-methyloctane
28. CH3
CH3 CH
H
C
CH3
H
C
H2
C
CH2 CH3
CH2 CH3
1.
2.
CH2
CH2 CH2 CH2 CH2 CH3 3.
CH3 CH2 C
CH2
CH2
H3C
CH3
CH
CH3
CH3 CH2 CH2 C
H
CH2 CH2 CH3
CH3
4.
C2H5
CHCH CHCH CHCHCHCH3 2 2 2 2
3
CH3
29.
30. Numbers are separated from each other
by commas;
Numbers are separated from names by
hyphens;
Prefixes di-, tri-, are not taken into
account in alphabetizing substituent
names.
31.
32. Step-by-step procedure to draw structural
formulas from the IUPAC names.
Consider the following IUPAC name:
3,3-Diethyl-5-methyldecane
33. Draw a decane skeleton and number it.
1 2 3 4 5 6 7 8 9 10
C C C C C C C C C C
34. Attach two ethyl groups at C-3
C2H5
1 2 3 4 5 6 7 8 9 10
C C C C C C C C C C
C2H5
35. Attach a methyl group at C.5
1 2 3 4 5 6 7 8 9 10
C C C C
H2
C C C C C C
CH2
CH2
CH3
H3C
CH3
36. Supply hydrogen atoms so that each carbon
atom has four bonds.
CH2
CH3 CH2 C
CH2
CH2
H3C
CH3
CH
CH3
CH2 CH2 CH2 CH2 CH3
39. •Alkanes whose carbon atoms are joined in rings
are called cycloalkanes.
•They have the general formula CnH2n
•They are named by attaching the prefix cyclo- to
the name of the alkane having the same number of
carbons as in the ring.
40. Cycloalkanes are often represented by
simple geometrical figures.
is represented by a
is represented by a
is represented by a
is represented by a
41. H2C
CH2
H2C
CH2
H2
C
C
H2
H2C
H2C
Cyclopropane Cyclopentane
It is understood that each corner represents
CH2 group.
42.
43.
44. Substituted Cycloalkanes are named as
•The substituent's on the ring are named
and their position is indicated by
numbers.
•The ring is numbered so that the
substituent's are given the lowest possible
numbers.
46. The ring is designed as a substituent if the
alkane chain contains a greater number of
carbon atoms than the ring.
CH2 CH2 CH2 CH3
1-Cyclopropylbutane and NOT Butylcyclopropane
47.
48. Alkenes have the general formula CnH2n
Contain at least one carbon-carbon
double bond. They are also called olefins
52. Select the longest continuous chain of carbon
atoms containing the double bond, as the parent
chain.
CH3
CH3 C
CH CH2 CH3
53. Name the longest chain. The name is obtained by
replacing “ane” of alkane with “ene”.
-ane
+ene
Pentene
CH3
CH3 C
CH CH2 CH3
54. Number the chain from the end closer to the
double bond.
CH3
CH3 C
CH CH2 CH3
1 2 3 4 5
55. Indicate the position of the double bond by the
number of the first (lowest numbered) carbon
atom involved in the double bond.
CH3
CH3 C
CH CH2 CH3
1 2 3 4 5
Carbon-2
56. Alkyl groups and other substituent's are
numbered , named and placed as prefixes in
alphabetical order.
CH3
CH3 C
CH CH2 CH3
1 2 3 4 5
2-Methyl-2-pentene or 2-Methylpent-2-ene
57. If more than one double bonds are found then use
the prefixes di,tri,tetra,for 2,3 and 4.
Alkenes containing two double bonds are named
as
58. H2C C CH2
1,2-Propadiene
H2C CH CH CH2
1,3-Butadiene or But-1,3-diene
59.
60. In naming Cycloalkenes, number the ring to give the
double bonded carbons the numbers 1 and 2 , choose
the direction of numbering so that the substituents
also get the lowest numbers.
CH3
Cyclohexene
1
2
3
4
5
3-Methylcyclopentene
The position of the double bond is not indicated
because it must be between
61.
62. Alkynes are hydrocarbons have the general
formula CnH2n-2 where
Alkynes contain at least one carbon-carbon triple
bond
65. HC CH CH3 C CH CH3 C C CH3
Ethyne Propyne 2-Butyne or But-2-yne
CH3 C C CH2 CH
CH3
CH3
5-Methyl-2-hexyne or 5-Methyl-hex-2-yne
and NOT 2-Meth2yl-4-hexyne
66. Select the longest continuous carbon chain
containing at least one triple bond, as the parent
chain.
CH3 C C CH2 CH
CH3
CH3
67. Name the longest chain. The name is obtained by
replacing ane of alkane with yne.
-ane
+yne
CH3 C C CH2 CH
CH3
CH3
68. Number the chain from the end closer to the triple
bond.
1 2 3 4 5 6
CH3 C C CH2 CH
CH3
CH3
69. Indicate the position of the triple bond by the
number of the first (lowest numbered) carbon atom
involved in the triple bond.
1 2 3 4 5 6
CH3 C C CH2 CH
CH3
CH3
Carbon -2
70. Alkyl groups and other substituents are
numbered, named and placed as prefixes in
alphabetical order.
1 2 3 4 5 6
CH3 C C CH2 CH
CH3
CH3
5-methyl-2-hexyne
71. If more than one triple are found then use the
prefixes di,tri,tetra,for 2,3 and 4.
Alkynes containing two triple bonds are named
as
HC C C CH
1,3-Butadiyne or But-1,3-diyne
72. They are classified as primary (1°), secondary (2°)
and tertiary ( 3°) alkyl halides.
73. Alkyl halides are named in the same way as alkanes
by treating the halogen as substituent on a parent
alkane chain.
Cl Cl
CH3CHCHCHCH2CH3
CH3
2,3-Dichloro-4-methylhexane
74. If different halogens are present, number each
according to its position on the chain and list them in
alphabetical order when writing the name.
Cl
BrCH2CH2CHCHCH3
CH3
1-Bromo-3-chloro-4-methylpentane
75. In addition to their systematic names, many simple
alkyl halides are also named by identifying first the
alkyl group and then the halogen.
For example,
CH3I can be called methyl iodide.
Such names are well entrenched in the chemical
literature and in daily usage.
78. Alcohols are compounds in which a hydroxyl
group (-OH) is bonded to a saturated carbon.
H3C OH
79. They are classified as primary (1°),
secondary (2°) and tertiary ( 3°) alcohols.
Primary alcohol H3C CH2 OH
CH3
CH3 CH
OH
CH3
CH3 C
OH
CH3
Secondary alcohol
Tertiary alcohol
80.
81. Select the longest continuous carbon chain to
which the hydroxyl group is attached as the
parent chain.
CH3
CH3CHCHCHCH2CH3
OH
CH3
82. Name the longest chain
The name is obtained by replacing the final -e with-ol.
-e
+ol
83. Number the chain to give the lowest number to
carbon attached to the hydroxyl group.
CH3
CH3 CH
CH2 CH2 OH
3-Methyl-1-butanol or 3-Methyl-but-1-ol
84. Other substituents are numbered, named, and
placed as prefixes in alphabetic order. For
example:
OH
CH3 OH CH3 CH2 OH CH3 CH
CH3
Methanol Ethanol
2-Propanol
CH3
CH3 CH
CH3
CH CH2 CH OH 3 CH
CH2 CH2 OH
CH3
3-Methyl-1-butanol or 3-Methyl-but-1-ol 4-Methyl-2-butanol or 4-Methyl-but-2-ol
85. Alcohols containing two or three –OH groups are
named as Alkanediols and Alkanetriols respectively.
Note that “–e” of the corresponding alkane name is
retained.
CH2 OH
CH2
CH2 OH
CH2 OH
CH
OH
CH2 OH
1,3-Propranediol or Propan-1,3-diol 1,2,3-Propanetriol or propan-1,2,3-triol
86. Select the longest chain containing the aldehyde
group.
Br
CH3 CH2 CH
O
CH2 C
H
87. Name the longest chain.
The name is obtained by dropping the final “-e”
from the name of the corresponding alkane, and
adding “-al” to the end.
Br
CH3 CH2 CH
O
CH2 C
H
88. Number the chain by assigning the number 1 to the
aldehyde carbon.
Br
CH3 CH2 CH
O
CH2 C
H
5 4 3 2 1
89. Other substituents are numbered, named, and
placed as prefixes in alphabetic order.
CH3
CH3 CH
O
CH2 C
H
3-Methyl
Br
CH3 CH2 CH
O
CH2 C
H
3-Bromo
90. When there are two aldehyde groups in a molecule,
it is named as “Alkanedial”.
Note that “-e” of the corresponding alkane name
is retained.
O
H C
O
CH2 CH2 CH2 C
H
1,5-Hexanedial
91. Ketones are compounds in which carbonyl group
(C=O) is bonded to two organic groups.
O
CH3 C
CH2 CH3
Butanone
O
CH3 C
CH3
Propanone
93. Name the longest chain by dropping “-e” from
the name of the corresponding alkane, and
Adding “-one” at the end.
94. Number the chain to give the lowest number to
the carbonyl carbon.
O
CH3 CH2 C
CH2 CH3
5 4 3 2 1
95. Other substituent's are numbered, named, and
placed as prefixes in alphabetic order.
CH3
CH3 CH
O
CH2 C CH3
5 4 3 2 1
4-Methyl-2-pentanone OR 4-Methyl pentan-2-one
96. When there are two carbonyl groups in a molecule,
it is named as Alkanedione.
O
CH3 C
O
CH2 C
CH2 CH3
2,4-Hexanedione
97. 1. Select the longest chain containing the acid
group -COOH.
2. Start numbering from the end where the
–COOH group is.
3. Remove “-e” from the parent alkane and
add “_oic acid”.
Eg.:-
CH3CH2COOH Propanoic acid
98. 4. If two carboxylic acid groups are present,
it should be named as alkanedioic acid
Eg.:-
HOOC-CH2-CH2-COOH Butanedioic acid
Other substituents are numbered, named, and
placed as prefixes in alphabetic order.
CH3CHCH2COOH
CH3
3-Methylbutanoic acid
99. Esters
They are the condensation products of
alcohols and acids.
CH3CH2COO H + HO CH2CH3 CH3CH2COO CH2CH3 + H2O
Fraction contains –COO- group
will have the name end with “ate”.
Fraction carries no –COO- group
will have the name end with “yl”
and will be written first.
The molecule is Ethyl propanoate
